Dissolve completely and then add
| Sodium sulphite | 2½ | ounces. |
| Potassium bromide | 15 | grains. |
Shake until completely dissolved but do not apply heat.
| B. | ||
| Potassium carbonate | 350 | grains. |
| Water | 8 | ounces. |
For use, mix three parts by measure of A and one part of B.
With this developer and a normal exposure, the image should appear in a few seconds and development should be complete in about two minutes. As fast as the prints are developed they should be immersed in
| Salt | 2 | ounces. |
| Water | 20 | ounces. |
to stop development. When all are developed, they must be rinsed for a minute or two in clean water and then fixed. Over-exposure is remedied by the addition of potassium bromide solution (as in the case of ferrous oxalate); under-exposed prints should be developed in a weak solution such as
| A | 3 | parts. |
| B | 1 | part. |
| Water | 4 | parts. |
Development will take longer, but the weaker solution will help to bring up the detail without the harshness of the shadows that would be the case if the normal developer was used.